RE: RATE Vol. II

Hi Robert, you wrote:
 
>>The best explanation of the data from radioactivity, an earth billions
of years old, may be too big a Goliath for this company of Davids to
slay. We'll see if they can find convincing evidence for an accelerated
rate of decay; I'm skeptical.<<
 
There is also good evidence for an ancient earth from various other
sources. I like this one, for example. I used this last night on a
team of YEC evangelists who just happened to pick my house and left
scratching their heads:
Hawaii
The Hawaiian Island chain is 3,700 miles long and 70 million years old.
Kilauea is the youngest of the subaerial volcanoes on the Island of
Hawaii and lies at the southeast end of the Hawaiian chain. The current
eruption of Kilauea began in 1983 located on the East Rift Zone, and
stands over 4,000 feet tall.
Hawaii itself consists of five connected volcanic mountains that were
built by a lava plume rising from the mantle. Kilauea, the world's
largest active volcano, is still rumbling because the island has yet to
move completely off the hot spot. The farther the other islands in the
chain are from Hawaii, the greater their age. About 150 miles to the
northwest is Oahu, which burst out of the sea about 3.5 million years
ago. Midway, one of the oldest islands in the chain, was formed between
15 and 25 million years ago.
About 2,000 miles from Hawaii, the chain abruptly veers and extends
north as a line of submerged volcanoes known as the Emperor Seamounts.
This suggests that the Pacific Plate changed course about 40 million
years ago. Where the chain's long march ends the volcanoes are more than
70 million years old. And, not surprisingly, off the southwestern coast
of the island of Hawaii, beneath the ocean surface, Loihi, the next
Hawaiian Island, is forming as the Pacific Plate continues its journey
over this hot spot.
The aging of the islands varies with the distance from the current hot
spot, where distance along the chain is approximated as distance away
from Kilauea volcano (the youngest above-sea-level Hawaiian volcano). In
fact, even beyond Kure the Hawaiian chain continues as a series of
now-submerged former islands known collectively as the Emperor
seamounts. The two primary volcanoes that make up Oahu (where Honolulu
is) have not erupted for well over a million years!
The age trend of the volcanoes is thought to be due to the way in which
the islands are built on the moving sea floor of the North Pacific
Ocean: the Pacific Ocean is mostly floored by a single tectonic plate
(known as the "Pacific Plate") that is moving over the layer in the
Earth known as the Asthenosphere. This movement takes it to the
northwest compared to the layers below it at a rate of 5 to 10 cm/yr
(the rate depends on where you are on it).
As the plate moves over a fixed spot deeper in the Earth where magma
(molten lava) forms, a new volcano can punch through this plate and
create an island. As the plate moves away, the volcano stops erupting
and a new one is formed in its place. With time, the volcanoes keep
drifting westward and getting older relative to the one active volcano
that is over the hot spot. As they age, the crust upon which they sit
cools and subsides. This, combined with erosion of the islands once
active volcanism stops, leads to a shrinking of the islands with age and
their eventual submergence below the ocean surface.
The distinctive linear shape of the Hawaiian Island-Emperor Seamounts
chain results from the Pacific Plate moving over a deep, stationary
hotspot in the mantle, located beneath the present-day position of the
Island of Hawaii. Heat from this hotspot produced a persistent source
of magma by partly melting the overriding Pacific Plate. The magma,
which is lighter than the surrounding solid rock, then rises through the
mantle and crust to erupt onto the seafloor, forming an active seamount.
Over time, countless eruptions cause the seamount to grow until it
finally emerges above sea level to form an island volcano. Continuing
plate movement eventually carries the island beyond the hotspot, cutting
it off from the magma source, and volcanism ceases. As one island
volcano becomes extinct, another develops over the hotspot, and the
cycle is repeated. This process of volcano growth and death, over many
millions of years, has left a long trail of volcanic islands and
seamounts across the Pacific Ocean floor. To the west of the Hawaiian
Islands, a line of sea mounts extends for thousands of miles growing
progressively smaller from the effects of millions of years of continual
underwater erosion.
Over the past 70 million years, the combined processes of magma
formation, volcano eruption and growth, and continued movement of the
Pacific Plate over the stationary Hawaiian "hot-spot" have left a long
trail of volcanoes across the Pacific Ocean floor. The Hawaiian
Ridge-Emperor Seamounts chain extends from the "Big Island" of Hawaii to
the Aleutian Trench off Alaska.
According to hotspot theory, the volcanoes of the Hawaiian chain should
get progressively older and become more eroded the farther they travel
beyond the hotspot. And this is the case. The oldest volcanic rocks on
Kauai, the northwestern most inhabited Hawaiian island, are about 5.5
million years old and are deeply eroded. By comparison, on the "Big
Island" of Hawaii - southeastern most in the chain and presumably still
positioned over the hotspot -- the oldest exposed rocks are less than
0.7 million years old, and new volcanic rock is continually being
formed.
The possibility that the Hawaiian Islands become younger to the
southeast was suspected by the ancient Hawaiians, long before any
scientific studies were done. During their voyages, sea-faring Hawaiians
noticed the differences in erosion, soil formation, and vegetation and
recognized that the islands to the northwest (Niihau and Kauai) were
older than those to the southeast (Maui and Hawaii).
 
This idea was handed down from generation to generation in the legends
of Pele, the fiery Goddess of Volcanoes. Pele originally lived on
Kauai. When her older sister Namakaokahai, the Goddess of the Sea,
attacked her, Pele fled to the Island of Oahu. When she was forced by
Namakaokahai to flee again, Pele moved southeast to Maui and finally to
Hawaii, where she now lives in the Halemaumau Crater at the summit of
Kilauea Volcano.
 
The mythical flight of Pele from Kauai to Hawaii, which alludes to the
eternal struggle between the growth of volcanic islands from eruptions
and their later erosion by ocean waves, is consistent with geologic
evidence obtained centuries later that clearly shows the islands
becoming younger from northwest to southeast.
 
Dick Fischer
Dick Fischer, Genesis Proclaimed Association
Finding Harmony in Bible, Science, and History
www.genesisproclaimed.org <http://www.genesisproclaimed.org/>
 
Received on Tue May 16 16:31:23 2006